Performance Water Pump Kit for GMC Envoy (2007-2009) 5.3L

High-Flow Water Pump Kit for 2007-2009 GMC Envoy (GMT360)

What it Does: The Performance Water Pump Kit replaces the failure-prone factory coolant pump and thermostat on the 2007-2009 Envoy to restore optimal coolant circulation and eliminate thermal runaway under load.

The Stock GMC Envoy Cooling System Limitations

The factory water pump installed on the GMT360 platform paired with the 5.3L LH6 Gen IV small-block V8 is notorious for premature shaft bearing wear and internal mechanical seal degradation. Heat cycling accelerates elastomer fatigue in the integrated thermostat housing gasket, while cavitation at higher engine RPM compromises impeller efficiency. Over time, coolant weeps past the internal relief port, leading to bearing contamination, severe belt misrouting load, fluid loss, and dangerous head gasket-threatening overheating events during heavy hauling or ambient summer heat soak.

The Engineering Solution

This replacement pump assembly features a precision-machined, heavy-duty cast aluminum housing engineered with reinforced bearing races and a high-efficiency cast impeller designed to maximize fluid velocity across the engine block. Outfitted with high-grade carbon-ceramic unitized shaft seals, it prevents fluid intrusion and eliminates pump bearing play. The kit includes an OEM-spec thermostat pre-assembled into an anti-corrosion housing, along with exact-fit rectangular and oval die-cut perimeter gaskets to eliminate interface weeping and maintain consistent line pressure across the cooling jackets.

What's Included

• 1 Engine Water Pump
• 1 Thermostat Housing
• 1 Thermostat
• 2 Rectangular Gaskets
• 1 Oval Gasket
• 2 Mounting Bolts

Technical Specifications

Compatibility

• 2007-2009 GMC Envoy 5.3L V8 (Denali, SLE, SLT)

Frequently Asked Questions & Fitment Warnings

Does this fit the GMT360 Envoy?

Yes, this is a direct fit for the 2007-2009 GMC Envoy equipped with the LH6 5.3L V8 engine; it does not fit models equipped with the 4.2L LL8 inline-six.

Do I need to bleed the cooling system after installing this pump?

Yes, thorough cooling system burping is mandatory to clear air pockets from the reverse-flow cylinder heads before operating the vehicle.

The GMC Heavy-Duty Caliber

Engineered to handle severe thermal loads, this pump assembly ensures continuous cooling performance whether towing trailers on steep highway grades or tackling daily stop-and-go commuting.